It has been observed that some language anomalies (dysphasia) or writing anomalies (dyslexia) are related to dysfunction in the auditive-verbal perception of the subject, which dysfunction appears during the development of language in the subject.
Various solutions have already been proposed for reeducating said perception. In particular, the Applicant's French Pat. No. 77 01 233, published under No. 2 377 189, suggests applying frequency modulation to an audio signal inversely to the modulation level of a pilot signal.
This prior installation has given only partial satisfaction, and the present invention seeks to improve it.